133 lines
2.4 KiB
Go

package email
import (
"fmt"
"net/smtp"
"os"
"strings"
"sync"
"time"
)
var (
global *Emailer
mu sync.RWMutex
)
type Emailer struct {
mode string
filePath string
host string
port string
username string
password string
}
type Email struct {
From string
To []string
Subject string
Body string
}
// Init initializes the global emailer with the provided settings
func Init(mode, filePath, host, port, username, password string) error {
mu.Lock()
defer mu.Unlock()
emailer := &Emailer{
mode: mode,
filePath: filePath,
host: host,
port: port,
username: username,
password: password,
}
if err := emailer.validate(); err != nil {
return err
}
global = emailer
return nil
}
// Get returns the global emailer instance (thread-safe)
func Get() *Emailer {
mu.RLock()
defer mu.RUnlock()
if global == nil {
panic("email not initialized - call Init first")
}
return global
}
// Send sends an email using the configured method (thread-safe)
func Send(email Email) error {
emailer := Get()
mu.RLock()
defer mu.RUnlock()
switch emailer.mode {
case "file":
return emailer.sendToFile(email)
case "smtp":
return emailer.sendViaSMTP(email)
default:
return fmt.Errorf("invalid email mode: %s", emailer.mode)
}
}
func (e *Emailer) validate() error {
if e.mode != "file" && e.mode != "smtp" {
return fmt.Errorf("mode must be 'file' or 'smtp'")
}
if e.mode == "smtp" {
if e.host == "" || e.username == "" || e.password == "" {
return fmt.Errorf("smtp mode requires host, username, and password")
}
}
if e.mode == "file" && e.filePath == "" {
return fmt.Errorf("file mode requires filePath")
}
return nil
}
func (e *Emailer) sendToFile(email Email) error {
content := fmt.Sprintf(`--- EMAIL ---
Time: %s
From: %s
To: %s
Subject: %s
%s
--- END EMAIL ---
`, time.Now().Format(time.RFC3339), email.From, strings.Join(email.To, ", "), email.Subject, email.Body)
f, err := os.OpenFile(e.filePath, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0644)
if err != nil {
return err
}
defer f.Close()
_, err = f.WriteString(content)
return err
}
func (e *Emailer) sendViaSMTP(email Email) error {
auth := smtp.PlainAuth("", e.username, e.password, e.host)
msg := fmt.Sprintf("From: %s\r\nTo: %s\r\nSubject: %s\r\n\r\n%s",
email.From,
strings.Join(email.To, ", "),
email.Subject,
email.Body,
)
addr := e.host + ":" + e.port
return smtp.SendMail(addr, auth, email.From, email.To, []byte(msg))
}